RESUMO
BACKGROUND: Preterm birth and low birthweight (LBW) might be associated with reduced physical fitness, although evidence remains inconclusive. OBJECTIVE: To examine the influence of preterm birth and LBW on physical fitness, as well as to assess whether variables such as gestational age, birthweight, or age at assessment moderate these effects. METHODS: PubMed, Scopus, and PsycINFO were systematically searched from inception to 7 December 2023 for case-control and cohort studies analyzing the association between preterm birth or LBW (or gestational age or birthweight as continuous variables) with at least one physical fitness-related outcome (i.e., cardiorespiratory fitness (CRF), muscle strength, flexibility, speed, agility). Random-effects meta-analysis and meta-regression models were used to estimate the pooled effect size, as well as to examine potential associations between the magnitude of the effect and gestational age, birthweight, or age at assessment. RESULTS: Fifty-two studies (n = 920,603 participants, average age ranging from 4.7 to 34.4 years) were included. Preterm birth was associated with reduced CRF (standardized mean difference (SMD) = -0.38, 95% confidence interval (CI) = -0.51 to -0.25) and muscle strength (SMD = -0.44, 95% CI = -0.79 to -0.08). LBW was associated with reduced CRF (SMD = -0.40, 95% CI = -0.64 to -0.17), muscle strength (SMD = -0.18, 95% CI = -0.24 to -0.13), flexibility (SMD = -0.11, 95% CI = -0.22 to -0.01), and agility (SMD = -0.99, 95% CI = -1.91 to -0.07). Meta-regression analyses showed that a lower gestational age or birthweight were associated with larger reductions in physical fitness, whereas no consistent association was found for the age at assessment. CONCLUSION: Both preterm birth and LBW seem associated with reduced physical fitness regardless of age, with larger reductions overall observed in individuals with lower gestational age or birthweight. These findings might support the implementation of preventive strategies (e.g., fitness monitoring and physical exercise interventions) in these populations through the life course. PROSPERO registration: CRD42021231845.
RESUMO
OBJECTIVES: School-based physical activity (PA) interventions have proven beneficial for improving cognitive performance and overall academic achievement, but their benefits on language skills remain unclear. We aimed to assess the effects of school-based PA interventions on language skills in children and adolescents. DESIGN: Systematic review with meta-analysis. METHODS: A systematic search was performed in PubMed, PsycINFO and Scopus until September 10th, 2022. We included randomized controlled trials (RCTs) that performed a school-based PA intervention in children/adolescents and that assessed language-related outcomes (i.e., reading, spelling, vocabulary, verbal fluency, comprehension and grammar) or language school grades. Random effect meta-analyses were conducted to pool study results. RESULTS: Thirty-one studies (18,651 participants) were finally included. Significant benefits were observed for reading (standardized mean difference [SMD]: 0.15; 95% confidence interval [CI]: 0.08, 0.22), vocabulary (SMD: 0.71; 95%CI: 0.44, 0.97), and comprehension (SMD: 0.24; 95%CI: 0.09, 0.40), with a non-significant trend (pâ¯=â¯0.083) also observed for language school grades (SMD: 0.40; 95%CI: -0.05, 0.86). No significant benefits were observed for spelling or verbal fluency (both pâ¯>â¯0.05), and no meta-analysis could be performed for grammar skills. No consistent differences were observed between integrated (i.e., performing PA along with the academic content) and non-integrated PA interventions (e.g., extra physical education lessons). CONCLUSIONS: School-based PA interventions appear as an effective strategy for improving different language-related skills, although further research is needed to determine how interventions' and participants' characteristics moderate these effects.
